Is there a schematic overview of Ubuntu's architecture?

as enthusiastic, advanced Linux learner, I'd love to get an overview about Linux' architecure/structure in general. You know, like "the big picture".

I'm thinking of a large schematic graphic showing what is what, who is who, what system (e.g. X) comprises which subsystems (GDM/Gnome/Compiz) on the way from a to z, from boot to interactive desktop, including the most important background services (auth, network, cron, ...).

Maybe a bit like this: http://www.flickr.com/photos/pgc/140859386/ but way more detailed. There's bootchart, which produces very comprehensive charts, but they again are too detailed and difficult to get the "big picture" from.

Is there such a thing? Possibly not for the whole System, but maybe for single subsystems?

I had trouble searching for this, because using search terms like "scheme" or "architecture" pointed to the wrong direction (a tool called "scheme" or CAD software for linux).

I appreciate any links. If there's interest in those schematic overviews and links, maybe someone could turn this post into a wiki post?

There are lots and lots of them. The more you want to know, the more diagrams you'll have to dig up.

This is one I made. But I gave up when I noticed that it's only ever going to get more complex, and I'll have to stop somewhere.

(note: this image probably contains a bunch of mistakes)

Use it as a guide to look in details at each of the subsystems (and notice that many are missing).

This, for example, is a diagram of the Linux Kernel structure:

(this image by Conan at en.wikipedia, licensed under cc-by)

Here's another one on xorg:

(source)

This is Moblins idea of the stack, it particularly highlights the relationships between the toolkits and APIs:

Between them, these diagrams cover a great portion of what's going on in Linux operating systems. As I said, if you want to know more about a specific subset of Ubuntu, you'll likely find a diagram that explains one particular thing in detail, rather than one massive one that explains everything. They are almost impossible to make.

_{Errata:
· There's a bunch of drivers in Ubuntu that are Kernel Modules instead of being compiled into the kernel.
· It looks like this GVFS business is all wrong in my diagram, I'm not completely sure
· The xorg diagram is by the people at wayland.freedesktop.org. Have a look to see what changes they're proposing}